The International Symposia on Hormonal Carcinogenesis (ISHC) is the premier international forum for both USA and foreign investigators dedicated to study the role of hormones and other growth regulators in the causation, promotion, and progression of hormone-associated cancers. Some of these neoplasms, specifically, breast, prostate, ovarian, and endometrial, represent the most prevalent cancers occurring in females and males in the USA and developed countries, and continue to be a major public health concern. These Symposia uniquely attract committed epidemiologists, basic scientists, and clinicians of diverse disciplines, such as cell and molecular biology, endocrinology, pharmacology, reproductive toxicology, pathology, gynecologic and urologic oncology, and epidemiology. Invited speakers are engaged in the cutting edge of hormone-related cancer and other areas of research, such as cell cycle, chromosome structure and function, epithelial-stroma interactions, genomics, and proteomics, which may have a direct bearing in leading to new developments in the field. The ISHC will be held in association with the University of Valencia Cancer Center in Valencia, Spain, June 21-25, 2003. Unique to this particular Symposium will be the integration of various disciplines within each session which bear on a single focused topic. This approach will foster a translational spirit. The seven sessions of this symposia include: 1. Breast Cancer I, Progesterone Action; 2. Breast Cancer II - Mechanisms of Genomic Instability; 3. Early In-Situ Lesions: Breast and Prostate Cancer; 4. Promotion and Prevention of Hormonal Cancers; 5. Prostate I - Androgen/Estrogen Action: 6. Prostate II - Androgen Receptor: Dependence and Resistance; and 7. Endometrium/Ovarian/ Colon Cancers. The program will also include a Plenary Symposium speaker, three State of the Art speakers, and two Poster Sessions (Epidemiology/Clinical and Molecular Biology/Metabolism). Junior investigators will be encouraged to participate in the Poster Sessions. Since these Symposia address the most recent advances in the field of hormonal carcinogenesis and hormone-dependent cancers, the proceedings will be published in book form for world-wide dissemination, as it has been in the past.